Effect of stripping frequency on turbot spawn quality.

Abstract

In production operations the application of daily examination of each female of broodstock should be a determinant progress in hatchery management in terms of fry output. The eggs expelled shortly after ovulation by means of a systematic fivefold a week stripping attempt of females, presented a high viability rate (72%) compared to that of eggs collected twice a week (46%) whereas the treatments did not have any effect on female fecundity. Increase of the stripping rhythm brought the hatching rates and broodstock fertilities respectively from 11% to 35% and from 20,000 to 65,000 larvae/kg of spawning female. The enhancement of egg quality and of the resulting larva production is discussed